Ply drawer - strong enough?

[John U]

Got a bit of a project going on. Using 12mm ply for it. It's going to be an open fronted shelf type thingo, with a slide out box inside (box is also part of the build).

Got the main bits together tonight, back not on yet, and It looks flimsy. It needs to support a clear plastic tucker box on top which might get up to 20kgs.

When the ply goes in to the back of it I guess it'll look a bit more solid.

I'm trying to keep it light. It's going to hold bulky but light stuff.

I purchased an enormous sheet of 12mm ply so have plenty to spare, but like I said, trying to keep the weight down.

Do I need to make it stronger?
Should it be OK for the weight it needs to carry on top?
Is there some weight efficient ways to make it stronger without compromising it's functionality too much?

Pics coming

 

[Albynsw]

Will wait for pics to better understand what you are doing but what I have done before is cap the front edge with 12x12 or 14x14 aluminium U channel ( you canget if from Bunnings in 1 and 3 metr lengths )
It stiffens up the front edge without increasing the bulk or you could add a timb edge support

 

[Triton14]

My mate is currently doing a removable fridge slide(enclosed fridge with ply to be able to store on top)/draw 12mm ply system for his Dmax.

I think he is using 12mm marine ply, which to me that makes sense for the non warp factor.

I guess you could also use a moisture resistant MDF board but think that would be a bit heavier??

I think the material can take a bit of weight, its the joins & bracing that count!

He uses this type of system for most of his joinery.

I would say he would also be using some metal bracing as well.

I use that Carinya material(also from bunnings) that comes in different sizes & shapes for projects & it works well.

Carinya 60 x 140 x 75mm Make-A-Bracket - single

Find Carinya 60 x 140 x 75mm Make-A-Bracket - single at Bunnings. Visit your local store for the widest range of products.

www.bunnings.com.au

 

[John U]

Pics up.

Gap down the right side is for fold up table.

Will be pushed to the front of the tray with the esky on tail gate side of it.

 

[John U]

I think he is using 12mm marine ply, which to me that makes sense for the non warp factor.

I was thinking the same until I saw the clip below. Started out with marine ply and swapped to normal ply. This bloke deals in ply and says there is no difference and marine is only necessary if you plan on building boats.

 

[cam04]

As @Albynsw says above, use ally angle screwed along the raw edges to hold it true - pic of my current Ute setup with exactly that below. Pardon the kid with the wierd facial expression haha.

Also, you can Swiss cheese the sides and base for weight loss, no problems at all. Think playschool windows etc. Ply is very strong.

 

[cam04]

“Swiss cheese” pic of the fridge cover I made for the last Ute. More material missing from the sides than remains. That setup was actually built in 2005 for my Colorado and then went into the ranger and lasted happily until 2021 and did many tours and much work.

 

[smitty_r51]

Not the best photos but mine 12mm ply did 10 years of travel without an issue and could lift it in and out on my own in the back of the wagon.

 

[John U]

Awesome!

Thanks everyone. Got a bunch of idea running around in my head now. Looks like I'll get some use out of that hole saw I bought for my snorkel install. Speed holes they used to call them in mountain biking. They weren't the safest way to reduce weight back then though

 

[CTL]

@cam04 mate, what brand of canopy on your BT? Outback touring at the mo and have finally convinced the bride that a canopy will be a good idea. Yours looks like a lift off? Is it dust proof?
Thanks

 

[Albynsw]

I was thinking the same until I saw the clip below. Started out with marine ply and swapped to normal ply. This bloke deals in ply and says there is no difference and marine is only necessary if you plan on building boats.

Years ago marine ply was made with a waterproof glue whereas standard ply used an interior grade glue. All ply now is made with a waterproof glue line so it is irrelevant in these type of situations.
Where the significant differences are is the type and grade of timber used and the amount of laminations used for the various thicknesses. Generally the more laminations the more stable the sheet will be. You will see the cheaper sheets have less laminations and will have one face side and the other side and internal layers will have imperfections, knots and holes in it
In the 9 and 12mm ply range Bunnings usually carries a low lamination ply that is not so flash. I look to other stockists when buying that thickness ply

 

[cam04]

@cam04 mate, what brand of canopy on your BT? Outback touring at the mo and have finally convinced the bride that a canopy will be a good idea. Yours looks like a lift off? Is it dust proof?
Thanks

Yes lift off. Completely dust proof and water proof. I’ll never have a tub again.
My canopy, drawers, under tray boxes and kitchen drawer are all renegade from trade tools. Less than $5k for the lot and I’m happy with it all. Prices look like they’ve gone up a bit.

I’ll throw up some links. We have accounts with these guys so it was just easy but the quality has been better than expected for the price.

The rain channel detail in the doors is fully rebated so it cannot leak even when they are open which seems to be an issue with some of the other brands.

TradeTools

www.tradetools.com

TradeTools

www.tradetools.com

TradeTools

www.tradetools.com

TradeTools

www.tradetools.com

 

[CTL]

@cam04 thanks heaps. When I get home I will follow up.

 

[Bru9]

My long term exp with bunnings marine ply is its consistently better quality than the standard ply, so thats why I use it. There is no practical diff to them both in general, however if the project is to be exposed to water its best to seal it with watery thin 2pack epoxy clear, the stuff at marine warhouse supplies etc. This prevents water getting the sides undermining the project. Avoid mdf and chipboard like the plauge! that stuff has so little strength.

20kgs is alot on the bumps, but im almost certain you could get away with 9mm ply, there is a few ways to get the structure really strong and tuff.

Below is how i transport an expensive oldschool induction fan without the corros destroying it. Inside is foam and pillows.

I used 6mm marine ply to keep weight down,
I then got a whole bunch of small stainless L brackets and screwed them to the inside corners and screwed stainless screws in, and grinded the excess length off the screws on outside. Dont use generic galvanized steel, its not as strong.
Then applied 4 thin coats of 2 pack epoxy all over to completely seal ply, doing this actually gives the whole project considerable strength and flex.
Then finally to stiffen up some of the large sides and in turn spread forces evenly over whole project, I glued (5min epoxy/arildite irrc) some lengths of 3x35mm stainless flat bar to the insides, again stainless is alot stronger and resistant than gal mild steel. Epoxy is super tuff and got flex so it will never come off. These techniques all get strength by so many individual particles acting at once. Even hot glue and pva glue can do wonders sometimes...

 

[John U]

Took on board a bit of advice from above. Cut outs and some brackets to strengthen up the front.

nearly done. Just need to paint it.

I don't have many screws left. Neither does Bunnings now

 

[hulsty]

Looking good, I've been running the same set of ply drawers across two cars for 15 years no issues. Dad has been using various different ply draws in his for ~30 years.

 

[dan637]

i was in the process of making some ply drawers and the some part of the wood got wet. its not much and hasn't swelled or distorted. it it still usable?

its 12mm exterior ply

 

[John U]

i was in the process of making some ply drawers and the some part of the wood got wet. its not much and hasn't swelled or distorted. it it still usable?

its 12mm exterior ply

Post up some pics mate.

I went complete overkill with my design. I wanted it to be able to support about 25 kgs of my transparent tucker box. It supports my currently heftier than normal weight with no problems. About 60 kgs more than what I needed it to.

 

[dan637]

 

[Albynsw]

The ply will be fine and only superficial damage